#!/usr/bin/python
# -*- coding: UTF-8 -*-

facto = 1
k = 100
result = 0

import time
start = time.clock()

while ( k > 0 ) :
  facto *= k
  k-=1

while ( facto > 0 ):
  result += facto % 10
  facto /= 10

print result


print "problem solved in ", (time.clock() - start), "s"

